Your work falls short of my expectations.你的工作未达到我的期望。

Please advise us of any change in your plan.你们的计划倘有变更,请告诉我们。

Have you brought your toothbrush with you?
你带牙刷来了吗?

Your pants are dirty.
你的裤子脏了。

I hope he doesn't mind your saying it.
我希望他不介意你说的话。

your是第二人称形容词性物主代词,单复数同形,在句中用作定语,也可用作动名词的逻辑主体。

Your work falls short of my expectations.你的工作未达到我的期望。

Please advise us of any change in your plan.你们的计划倘有变更,请告诉我们。

Have you brought your toothbrush with you?
你带牙刷来了吗?

Your pants are dirty.
你的裤子脏了。

I hope he doesn't mind your saying it.
我希望他不介意你说的话。